The product rate variation problem minimizes the variation in the rate at which different models of a common base product are produced on the assembly lines with the assumption of negligible switch-over cost and unit processing time for each copy of each model. The assumption of significant setup and arbitrary processing times forces the problem to be a two phase problem. The first phase determ...

We consider the linear recurrence relation Vt (x)=∑mi=1(aix+bi )Vt−i(x)+ cx+f wherem> 1, ai and bi , 16 i 6m, are integers. The RSA and LUC schemes can be defined by this relation. In this paper we show that if the linear recurrence relation has some properties, the public-key scheme based on it cannot withstand the common modulus and chosen-message attacks, no matter what the order m is and wh...

In swimming sharks, vertebrae are subjected, in part, to compressive loads as axial muscles contract. We currently have no information about which vertebral elements, centra, arch cartilages, or both, actually bear compressive loads in cartilaginous vertebrae. To address this issue, the goal of this experiment was to determine the load-bearing ability of arch and centrum cartilages in compressi...

We prove that the property " P doesn't make the old reals Lebesgue null " is preserved under countable support iterations of proper forcings, under the additional assumption that the forcings are nep (a generalization of Suslin proper) in an absolute way. We also give some results for general Suslin ccc ideals. Hypothesis 1: Let (P β , ˜ Q β) β<< be a countable support iteration of proper forci...

In the present paper Artificial Neural Networks (ANN) are applied in order to predict the buckling modes of thin-walled PVC tubes under compressive axial forces. For the development of the models the neural network toolbox of Matlab ® was applied. The results show that these models can satisfactorily face these problems and they constitute not only a fast method, compared to time consuming expe...